NEW YORK • For the newly crowned National Basketball Association (NBA) champion LeBron James, living and working in the same place for more than three months "played with your mind" and "played with your body".

Phoenix Suns coach Monty Williams marvelled most at a statistic - zero coronavirus-related postponements during the league's grand sports and social experiment.

Adam Silver, the commissioner of the NBA, called it a triumph that required "extraordinary sacrifices by everyone involved".

Seven months after halting play as the pandemic surged across the United States, the NBA concluded its season in a restricted-access bubble at Walt Disney World near Orlando, Florida.

The league tested players for the virus daily. It imposed strict rules and occasionally doled out penalties to ensure that 113 pages of health and safety protocols were followed. Long bouts of isolation and the resultant mental and emotional strain prompted Rajon Rondo, James' Los Angeles Lakers teammate, to deem this "by far" the hardest postseason of his 14-year career.

Yet it also worked. The bubble held for 96 days, and when players leaguewide refused to play in a gesture of civil rights protest during the first round of the play-offs, league officials and team owners pledged to do more to support social justice causes.

The restarted season, which began amid considerable scepticism, ultimately delivered a televised spectacle with a Hollywood ending, as the Lakers emerged with the franchise's 17th NBA title. It was James' fourth.

Now thorny discussions loom between league officials and the players' union to address an array of unknowns about next season. What is certain is that the players have been promised eight weeks' notice before they have to start anew.

Silver has said he doesn't expect the new season to start before January. While there is a strong desire on both sides to see teams play in their home markets, preferably with a small number of fans admitted to games, it remains unclear how soon it will be safe to do so.

The NBA draft is set for Nov 18, and the league's US$180 million (S$244.6 million) bubble allowed it to crown a champion for the 74th year while also satisfying some agreements with television partners. Yet there is much to resolve.

The league and the union must decide when to start free agency and how long they can hold out for a return to home markets before conceding that short-term regional bubbles may be necessary to play.

They must also establish a new salary cap and luxury tax amid the pinch of a US$1.5 billion shortfall in projected revenue from this season.

At least the sides head into this off season with the momentum that flows from finding a creative solution to stay operational.

The NBA was the first major North American sports league to suspend operations in March in response to the coronavirus outbreak.

After a four-month stoppage, 22 of the league's 30 teams were summoned to one site for the first time in league history. No one was allowed to leave the campus once inside without league authorisation, and fans were barred from venues.

Each day, players, coaches and staff members were tested for the virus. They were also governed by social distancing regulations during meal times and leisure activities.

There was pushback about the constraints from the inside - "I feel like when we got in the bubble, everyone was complaining about not wanting to be here," Miami's Bam Adebayo said - but players also wanted to use the visibility of the NBA's comeback to support their social advocacy.

There were roughly 1,500 campus residents at the bubble's peak, but the league managed to stage 172 regular-season and play-off games without a serious coronavirus threat.

Silver's Sept 30 statement said that the league had registered "no cases" of the coronavirus among representatives of the 22 teams and NBA personnel who began reporting to the campus on July 7.

The only stoppage of was not health-related. The Milwaukee Bucks walked out before an Aug 26 play-off game against the Orlando Magic in response to the police shooting of Jacob Blake in Wisconsin. That led to a three-day shutdown - with a cancellation of the rest of the season averted.

Further "difficult negotiations" between the league and the union, as Silver described them at a news conference, await for next season's terms. The sides, though, could also use a break after a season that lasted a whopping 380 days.

It took a bubble with unforeseen durability, so sturdy that "bubble" is now a common word in the NBA lexicon, to shepherd everyone through the past three months to fashion a finish to the longest, most turbulent season in league history.

NYTIMES